ALSA: soc - Remove obsoleted sound/driver.h inclusion

Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/soc/pxa/em-x270.c

@@ -23,7 +23,6 @@
 #include <linux/moduleparam.h>
 #include <linux/device.h>
 
-#include <sound/driver.h>
 #include <sound/core.h>
 #include <sound/pcm.h>
 #include <sound/soc.h>